Electric motors are widely used in the production of many different types of products. Pumps for refrigeration, fans, water wells, hand tools, and even electric propulsion for various types of motor vehicles are widely adopted.
In general, electric motors produce mechanical work based on some manipulation of one or more magnetic fields. Magnetic fields are associated with electrical current. Under proper circumstances, the energy stored in a magnetic field by a current can be translated into mechanical torque on a rotating shaft, or thrust in a linear system. Torque or thrust represent a mechanical force that can accelerate or decelerate an object.
In general, rotating motors may easily outnumber linear motors. There are several types of rotating motors. For example, DC (direct current) motors can operate from a DC voltage or current source, such as a battery. Induction and synchronous motors may call for a time-varying excitation (e.g., AC) to couple flux through a small air gap between a rotor and a stator. Reluctance motors may produce torque based on preferred paths for a magnetic field through a core, for example.